| // Copyright (C) 2020 The Android Open Source Project |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package com.google.gerrit.plugins.codeowners.backend; |
| |
| import static com.google.common.collect.ImmutableList.toImmutableList; |
| import static java.util.Objects.requireNonNull; |
| |
| import com.google.common.collect.ImmutableList; |
| import com.google.common.flogger.FluentLogger; |
| import com.google.gerrit.common.Nullable; |
| import com.google.gerrit.entities.Project; |
| import com.google.gerrit.metrics.Timer0; |
| import com.google.gerrit.plugins.codeowners.backend.config.CodeOwnersPluginConfiguration; |
| import com.google.gerrit.plugins.codeowners.common.ChangedFile; |
| import com.google.gerrit.plugins.codeowners.common.MergeCommitStrategy; |
| import com.google.gerrit.plugins.codeowners.metrics.CodeOwnerMetrics; |
| import com.google.gerrit.server.change.RevisionResource; |
| import com.google.gerrit.server.config.GerritServerConfig; |
| import com.google.gerrit.server.git.GitRepositoryManager; |
| import com.google.gerrit.server.git.InMemoryInserter; |
| import com.google.gerrit.server.git.MergeUtil; |
| import com.google.gerrit.server.patch.AutoMerger; |
| import com.google.gerrit.server.patch.PatchListNotAvailableException; |
| import com.google.inject.Inject; |
| import com.google.inject.Provider; |
| import com.google.inject.Singleton; |
| import java.io.IOException; |
| import java.util.List; |
| import org.eclipse.jgit.diff.DiffEntry; |
| import org.eclipse.jgit.diff.DiffFormatter; |
| import org.eclipse.jgit.diff.RawTextComparator; |
| import org.eclipse.jgit.lib.Config; |
| import org.eclipse.jgit.lib.ObjectId; |
| import org.eclipse.jgit.lib.ObjectReader; |
| import org.eclipse.jgit.lib.Repository; |
| import org.eclipse.jgit.merge.ThreeWayMergeStrategy; |
| import org.eclipse.jgit.revwalk.RevCommit; |
| import org.eclipse.jgit.revwalk.RevWalk; |
| import org.eclipse.jgit.util.io.DisabledOutputStream; |
| |
| /** |
| * Class to compute the files that have been changed in a revision. |
| * |
| * <p>The file diff is newly computed on each access and not retrieved from any cache. This is |
| * better than using {@link com.google.gerrit.server.patch.PatchListCache} which does a lot of |
| * unneeded computations and hence is slower. The Gerrit diff caches are currently being redesigned. |
| * Once the envisioned {@code ModifiedFilesCache} is available we should consider using it. |
| */ |
| @Singleton |
| public class ChangedFiles { |
| private static final FluentLogger logger = FluentLogger.forEnclosingClass(); |
| |
| private static int MAX_CHANGED_FILES_TO_LOG = 25; |
| |
| private final GitRepositoryManager repoManager; |
| private final CodeOwnersPluginConfiguration codeOwnersPluginConfiguration; |
| private final Provider<AutoMerger> autoMergerProvider; |
| private final CodeOwnerMetrics codeOwnerMetrics; |
| private final ThreeWayMergeStrategy mergeStrategy; |
| |
| @Inject |
| public ChangedFiles( |
| @GerritServerConfig Config cfg, |
| GitRepositoryManager repoManager, |
| CodeOwnersPluginConfiguration codeOwnersPluginConfiguration, |
| Provider<AutoMerger> autoMergerProvider, |
| CodeOwnerMetrics codeOwnerMetrics) { |
| this.repoManager = repoManager; |
| this.codeOwnersPluginConfiguration = codeOwnersPluginConfiguration; |
| this.autoMergerProvider = autoMergerProvider; |
| this.codeOwnerMetrics = codeOwnerMetrics; |
| this.mergeStrategy = MergeUtil.getMergeStrategy(cfg); |
| } |
| |
| /** |
| * Computes the files that have been changed in the given revision. |
| * |
| * <p>The diff is computed against the parent commit. |
| * |
| * @param revisionResource the revision resource for which the changed files should be computed |
| * @return the files that have been changed in the given revision, sorted alphabetically by path |
| * @throws IOException thrown if the computation fails due to an I/O error |
| * @throws PatchListNotAvailableException thrown if getting the patch list for a merge commit |
| * against the auto merge failed |
| */ |
| public ImmutableList<ChangedFile> compute(RevisionResource revisionResource) |
| throws IOException, PatchListNotAvailableException { |
| requireNonNull(revisionResource, "revisionResource"); |
| return compute(revisionResource.getProject(), revisionResource.getPatchSet().commitId()); |
| } |
| |
| /** |
| * Computes the files that have been changed in the given revision. |
| * |
| * <p>The diff is computed against the parent commit. |
| * |
| * @param project the project |
| * @param revision the revision for which the changed files should be computed |
| * @return the files that have been changed in the given revision, sorted alphabetically by path |
| * @throws IOException thrown if the computation fails due to an I/O error |
| * @throws PatchListNotAvailableException thrown if getting the patch list for a merge commit |
| * against the auto merge failed |
| */ |
| public ImmutableList<ChangedFile> compute(Project.NameKey project, ObjectId revision) |
| throws IOException, PatchListNotAvailableException { |
| requireNonNull(project, "project"); |
| requireNonNull(revision, "revision"); |
| |
| try (Repository repository = repoManager.openRepository(project); |
| RevWalk revWalk = new RevWalk(repository)) { |
| RevCommit revCommit = revWalk.parseCommit(revision); |
| return compute(project, repository.getConfig(), revWalk, revCommit); |
| } |
| } |
| |
| public ImmutableList<ChangedFile> compute( |
| Project.NameKey project, Config repoConfig, RevWalk revWalk, RevCommit revCommit) |
| throws IOException { |
| return compute( |
| project, |
| repoConfig, |
| revWalk, |
| revCommit, |
| codeOwnersPluginConfiguration.getProjectConfig(project).getMergeCommitStrategy()); |
| } |
| |
| public ImmutableList<ChangedFile> compute( |
| Project.NameKey project, |
| Config repoConfig, |
| RevWalk revWalk, |
| RevCommit revCommit, |
| MergeCommitStrategy mergeCommitStrategy) |
| throws IOException { |
| requireNonNull(project, "project"); |
| requireNonNull(repoConfig, "repoConfig"); |
| requireNonNull(revWalk, "revWalk"); |
| requireNonNull(revCommit, "revCommit"); |
| requireNonNull(mergeCommitStrategy, "mergeCommitStrategy"); |
| |
| logger.atFine().log( |
| "computing changed files for revision %s in project %s", revCommit.name(), project); |
| |
| if (revCommit.getParentCount() > 1 |
| && MergeCommitStrategy.FILES_WITH_CONFLICT_RESOLUTION.equals(mergeCommitStrategy)) { |
| RevCommit autoMergeCommit = getAutoMergeCommit(project, revCommit); |
| return compute(repoConfig, revWalk, revCommit, autoMergeCommit); |
| } |
| |
| RevCommit baseCommit = revCommit.getParentCount() > 0 ? revCommit.getParent(0) : null; |
| return compute(repoConfig, revWalk, revCommit, baseCommit); |
| } |
| |
| private RevCommit getAutoMergeCommit(Project.NameKey project, RevCommit mergeCommit) |
| throws IOException { |
| try (Timer0.Context ctx = codeOwnerMetrics.getAutoMerge.start(); |
| Repository repository = repoManager.openRepository(project); |
| InMemoryInserter inserter = new InMemoryInserter(repository); |
| ObjectReader reader = inserter.newReader(); |
| RevWalk revWalk = new RevWalk(reader)) { |
| return autoMergerProvider |
| .get() |
| .lookupFromGitOrMergeInMemory(repository, revWalk, inserter, mergeCommit, mergeStrategy); |
| } |
| } |
| |
| /** |
| * Computes the changed files by comparing the given commit against the given base commit. |
| * |
| * <p>The computation also works if the commit doesn't have any parent. |
| * |
| * @param repoConfig the repository configuration |
| * @param revWalk the rev walk |
| * @param commit the commit for which the changed files should be computed |
| * @param baseCommit the base commit against which the given commit should be compared, {@code |
| * null} if the commit doesn't have any parent commit |
| * @return the changed files for the given commit, sorted alphabetically by path |
| */ |
| private ImmutableList<ChangedFile> compute( |
| Config repoConfig, RevWalk revWalk, RevCommit commit, @Nullable RevCommit baseCommit) |
| throws IOException { |
| logger.atFine().log("baseCommit = %s", baseCommit != null ? baseCommit.name() : "n/a"); |
| try (Timer0.Context ctx = codeOwnerMetrics.computeChangedFiles.start()) { |
| // Detecting renames is expensive (since it requires Git to load and compare file contents of |
| // added and deleted files) and can significantly increase the latency for changes that touch |
| // large files. To avoid this latency we do not enable the rename detection on the |
| // DiffFormater. As a result of this renamed files will be returned as 2 ChangedFile's, one |
| // for the deletion of the old path and one for the addition of the new path. |
| try (DiffFormatter diffFormatter = new DiffFormatter(DisabledOutputStream.INSTANCE)) { |
| diffFormatter.setReader(revWalk.getObjectReader(), repoConfig); |
| diffFormatter.setDiffComparator(RawTextComparator.DEFAULT); |
| List<DiffEntry> diffEntries = diffFormatter.scan(baseCommit, commit); |
| ImmutableList<ChangedFile> changedFiles = |
| diffEntries.stream().map(ChangedFile::create).collect(toImmutableList()); |
| if (changedFiles.size() <= MAX_CHANGED_FILES_TO_LOG) { |
| logger.atFine().log("changed files = %s", changedFiles); |
| } else { |
| logger.atFine().log( |
| "changed files = %s (and %d more)", |
| changedFiles.asList().subList(0, MAX_CHANGED_FILES_TO_LOG), |
| changedFiles.size() - MAX_CHANGED_FILES_TO_LOG); |
| } |
| return changedFiles; |
| } |
| } |
| } |
| } |